608
FXUS65 KBYZ 101110
AFDBYZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BILLINGS MT
510 AM MDT FRI JUL 10 2026
KEY MESSAGES
- EXTREME HEAT EXPECTED THIS WEEKEND. HIGH TEMPERATURES EXCEEDING
100 DEGREES WITH OVERNIGHT LOW TEMPERATURES IN THE 60S AND 70S
WILL PRODUCE CUMULATIVE HEAT STRESS.
- HIGH TEMPERATURES ON SUNDAY MAY CHALLENGE ALL-TIME RECORDS AT
ALL CLIMATE SITES.
- SLIGHT CHANCE OF SHOWERS, AND MAYBE A FEW WEAK THUNDERSTORMS,
THIS AFTERNOON AND EVENING.
UPDATE
SATELLITE IMAGERY SHOWS MOSTLY CLEAR SKIES OVER THE REGION AS HIGH
PRESSURE BEGINS TO BUILD FROM THE SOUTH. THERE IS A WEAK SHORTWAVE
LIFTING OUT OF THE NORTHERN GREAT BASIN THAT SHOULD HELP TO
PRODUCE ISOLATED WEAK T-STORMS THIS AFTERNOON AND EVENING, AS CAMS
CONTINUE TO SHOW. THE ONLY RISK WITH TODAY'S CONVECTION WILL BE
ERRATIC WIND GUSTS. TEMPS WILL CLIMB INTO THE WIDESPREAD 90S
TODAY, WITH 100F POSSIBLE AT NOTORIOUSLY HOTTER LOCATIONS LIKE
MILES CITY AND BRANDENBERG. THE REAL HEAT COMES THIS WEEKEND. HAVE
UPGRADED THE WATCH TO AN EXTREME HEAT WARNING. FORECAST IS IN
GOOD SHAPE. JKL
DISCUSSION
THROUGH THURSDAY...
CONDITIONS TREND WARMER TODAY AS RIDGING BUILDS INTO THE REGION,
BRINGING HIGH TEMPERATURES INTO THE UPPER 80S TO 90S FOR MANY
LOCATIONS. WHILE MOSTLY DRY CONDITIONS WILL PREVAIL, SOME WEAK
ENERGY MOVING IN FROM THE SOUTHWEST MAY PROVIDE ENOUGH FORCING TO
GENERATE HIGH-BASED SHOWERS AND WEAK THUNDERSTORMS DURING THE
AFTERNOON AND EVENING (15 PERCENT CHANCE). WITH THIS, GUSTY AND
ERRATIC WINDS MAY DEVELOP WITH DRY AIR IN PLACE NEAR THE SURFACE.
THIS WEEKEND THROUGH MONDAY, THERE CONTINUES TO BE HIGH
CONFIDENCE IN HOT TO VERY HOT TEMPERATURES AS A STRONG RIDGE OF
HIGH PRESSURE BUILDS OVER THE REGION. ENSEMBLES SUGGEST 500MB
HEIGHTS APPROACHING 596-600 DM FOR SUNDAY. HIGH TEMPERATURES OF 95
TO 112 DEGREES ARE FORECAST, WARMEST ON SUNDAY WITH VERY WARM
TEMPERATURES ALOFT (700MB TEMPERATURES NEAR OR EXCEEDING 20C BY
SUNDAY AND 850 MB TEMPERATURES OF 35-40C). THERE CONTINUES TO BE A
MODERATE CHANCE AT EXCEEDING 110 DEGREES FOR AREAS ROUGHLY FROM
BILLINGS EAST. TEMPERATURES THIS WARM COULD THREATEN ALL-TIME
RECORD HIGH TEMPERATURES AT ALL CLIMATE SITES ON SUNDAY. ALONG
WITH THE HOT DAYTIME TEMPERATURES, OVERNIGHT LOW TEMPERATURES IN
THE 60S AND 70S, WARMEST SUNDAY NIGHT, WILL EXACERBATE THE RISK OF
HEAT STRESS.
ALONG WITH THE HEAT, VERY DRY CONDITIONS WILL EXIST, WITH
RELATIVE HUMIDITY VALUES DECREASING INTO THE SINGLE DIGITS TO
TEENS PERCENT SATURDAY AND SUNDAY, AND TEENS TO 20S PERCENT
MONDAY. BREEZY SOUTH TO SOUTHWEST WINDS LOOK TO DEVELOP OVER
WESTERN AND CENTRAL AREAS (GUSTS 20S TO 30S MPH) DURING THE DAY ON
SUNDAY, AHEAD OF A COLD FRONT FROM THE NORTHWEST SUNDAY
EVENING/NIGHT. THE COMBINATION OF BREEZY WINDS, VERY HOT
TEMPERATURES, AND VERY DRY CONDITIONS WILL INCREASE FIRE WEATHER
CONCERNS. TAKE CARE NOT TO CAUSE A SPARK.
HEADING INTO TUESDAY AND THE MIDDLE OF NEXT WEEK, THE RIDGE IS
PROGGED BY ENSEMBLES TO SHIFT EAST A BIT, ALLOWING TEMPERATURES TO
COOL SLIGHTLY (HIGHS IN THE 90S), AND MONSOONAL MOISTURE TO MOVE
IN FROM THE SOUTHWEST. THIS WOULD ALLOW FOR DAILY LOW TO MODERATE
SHOWER/THUNDERSTORM CHANCES TO RETURN TO THE AREA ALONG WITH
HIGHER RELATIVE HUMIDITY VALUES. ENSEMBLES PROG PWATS IN EXCESS OF
AN INCH FOR MUCH OF THE AREA FROM TUESDAY ONWARD.
BELOW ARE THE ALL-TIME RECORD HIGH TEMPERATURES AT EACH OF OUR
CLIMATE STATIONS:
BILLINGS, MT 108F
LIVINGSTON, MT 105F
MILES CITY, MT 111F
SHERIDAN, WY 107F
BAKER, MT 109F
STP
AVIATION
ISSUED 11Z. VFR WILL PREVAIL ACROSS THE REGION TODAY AND TONIGHT,
WITH MOSTLY LIGHT WINDS. EXPECT ISOLATED HIGH-BASED WEAK
THUNDERSTORMS THIS AFTERNOON AND EVENING (MAINLY FROM 20-04Z) THAT
COULD PRODUCE ERRATIC SURFACE WIND GUSTS TO ~30KTS. KSHR IS THE
MOST LIKELY TAF SITE TO SEE A THUNDERSTORM, BUT CONFIDENCE IS
QUITE LOW SO HAVE NOT ADDED TS TO ANY TAF SITE. JKL
PRELIMINARY POINT TEMP/POPS
TDY SAT SUN MON TUE WED THU
-------------------------------------------------------
BIL 097 065/104 068/109 072/099 071/096 069/092 067/093
1/U 10/G 00/G 00/U 01/U 42/T 32/T
LVM 094 056/101 059/107 062/098 062/092 060/091 058/090
2/T 20/G 00/G 00/U 12/T 54/T 42/T
HDN 098 061/104 065/110 071/100 069/099 068/094 066/094
1/U 20/G 00/G 00/U 01/U 22/T 31/U
MLS 099 066/105 068/111 075/101 068/099 068/093 067/093
0/U 10/G 00/G 00/G 00/U 21/U 21/U
4BQ 098 068/102 068/108 076/103 069/100 070/094 068/093
2/T 20/G 00/G 00/G 00/U 11/U 32/T
BHK 095 065/102 067/107 073/101 065/097 065/091 063/091
1/U 11/G 00/G 00/G 00/U 21/U 31/U
SHR 095 058/102 061/106 069/099 064/097 065/091 062/090
2/T 20/G 00/N 00/U 01/U 14/T 44/T
BYZ WATCHES/WARNINGS/ADVISORIES
MT...EXTREME HEAT WARNING IN EFFECT FROM 6 AM SATURDAY TO MIDNIGHT
MDT MONDAY NIGHT FOR ZONES
29>34-36-37-40-42-56>58-63>66-138-139-141-169-170-172-173-228-235.
WY...EXTREME HEAT WARNING IN EFFECT FROM 6 AM SATURDAY TO MIDNIGHT
MDT MONDAY NIGHT FOR ZONE 199.
WEATHER.GOV/BILLINGS
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